JACK RENDULICH/AP
The US Air Force has awarded a contract to Lockheed Martin for a hypersonic weapon, the second such contract this year.
The request comes just one week after China tested a hypersonic aircraft that some experts believe can carry both conventional and nuclear payloads and evade existing missile defenses.
The hypersonic arms race is heating up as Russia, China, and the US compete to field weapons that travel upwards of five times the speed of sound.
The US Air Force is...